Spring lock for incandescent lamps



F. H. owENs SPRING Loox Fon INcArmEscENT LAMPS Filed llarch 17, 1926 @Mmmmwwmwmmm INVENTOR. j'zlJg-wgm) 'ATTORNE atented Aug. 28, 1.928.

UNITEDv STATES FREEMAN H. OWENS, F NEW YORK, N. Y.

SPRING LOCK FOR INCANDESCENT LAMPS.

Application mea March 17, 1926. serial No'. 95,304.

My invention relates broadly to incandescent lamps and more particularly to a spring lock for preventing the loosening and extinguishing of lamps by vibration.

One of the objects of my invention is to provide a construction of spring loc k for preventing the loosening and extinguishing ot' incandescent lamps under conditions of vibration, which may be readily manufactured inexpensively on a quantity productlon basis.

Another object of my invention is to provide a spring lock device which may be readlili ily applied to incandescent lamps and sockets, ot' standard construction with only slight modification, making it unnecessary tocincrease the cost of the lamp or socket construction to any substantial degree.

My invention will be more clearly understood from the specification hereinafter following by reference to the accompanying drawings in which Figure 1 shows an incandescent lamp and socket mounting therefor with the lamp removed from' the socket and showing the application of the spring lock ot my invention; Fig. 2 illustrates an incandescent lamp which has been screwed into the lamp socket and locked against accidental unscrewing by virtue of the locking device of my invention; Fig. 3 is a crosssectional view taken on line 3-3 of Fig. 1 through the base of an incandescent lamp constructed in accordance with my invention; Fig. 4 is a cross-sectional view taken through the base of the incandescent lamp in locked position within the lamp socket on line 4-4 of Fig. 2; and Fig. 5 is a perspective view of the spring lock arrangement which cooperates with indentations in the screw threads on the base of a lamp for preventing the unscrewing of the lamp from the base under conditions of vibration.

l am familiar with various constructions of locking devices for preventing theft of` a lam in the socket. I provide a plurality ot inc entations along the screw threads on the base of the lamp with a cooperating spring device carried by the lamp socket which resiliently interlocks with the indentations in the base of the lamp for preventing the turning ot' the lamp in its socket underl conditions of vibration.

Referring to the drawings in more detail reference character 1 designates a socket shell for an incandescent lamp with an interiorly screw threaded shell therein to receive the base 5 of an incandescent lamp 4. The screw threaded shell 2 is apertured at 3 with the aperture extending over a width substantially larger than the width of one thread 6 o'n the base of the lamp 5. The base 5 of the incandescent lamp 4 is provided with parallel extending rows of indentations 7, 8, 9, 1() and 11 formed in the screw thread 6 of the base 5. Around the outside of the shell 2 l provide a resilient wire device, shown more clearly in Fig. 5, having circular portions 12 integrally related to a substantially U shaped head 13 which extends through the aperture 3 in the shell 2 and terminating in ends 14. The wire like member 12, 13 and 14 is substantially a spring coil which tends to grip the outside of the shell 2 and exert an inward pressure through aperture 3. lThe resilient locking head 13 engages the detents 7, 8, 9, 10 and 11 .as the lamp is screwed into its socket and tends to prevent rotation of the lamp in the socket under conditions of vibration. The resilient head 13, however, is readily moved outwardly and the detents disengaged therefrom when applying a positive rotative force of relatively large magnitude to the lamp when it is to be manually removed from the socket for replacement.

My invention finds particular application in incandescent lamp lighting installations on shipboard, railroad trains and in other instances Where the lighting installation is subject to continuous shock vibration. I have found in many instances that lamps in the usual form' of incandescent lamp sockets unscrew of their own accord under conditions ot continuous vibration, with the result that the lamp is extinguished. The construction of spring locking device of my invention is such that it may be readily manu tactured inexpensively on a quantity production basis. The resilient wire device snugly conforms with the contour of the screw threads on the outside of the lamg socket enablin standard parts to be use with substantia 1y no modifications. The resilient wire member is given a pitch substantially e ual to the pitch of the screw threads ont e exterior of the socket so that the member may be screwed into place on the outside of the socket.

While I have described my invention in a certain particular embodiment I desire that it be understood that modifications may be made and that I intend no limitations upon my invention other than are imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is as follows:

1. A springlocking device for incandescent lamps having a threaded base adapted to engage a. screw threaded socket, said locking device including a plurality' of rows of indentations formed in the screw threaded base of said lamp and a spring wire member having portions bent upon themselves forminga pair of parallel extending portions encirclingr said screw threaded socket and passing through an aperture therein for engaging the indentations formed in said screw threaded base for reventing said base from turning in saidsocket under conditions of shock vibration.

2. A spring locking device vfor incandescent lamps having a screw threaded base for engaging a screw threaded socket comprising a spring wire member doubled upon itself and encircling said socket and passing through an aperture in one side thereof, a plurality of indentations formed on the screw threaded base of said lamp, said spring device operated to engage said indentations through said aperture for preventing the unscrewing of said base under conditions of shock vibration.

3. A locking device for incandescent lamps having a screw threaded base adapted to engage a screw threaded socket, said locking device including a plurality of indentations formed in said screw threaded base and a spring wire member having a pair of parallel extending portions encircling said screw threaded socket and extending through one wall thereof for engaging the indentations formed in said screw threaded base when said incandescent lamp is screwed into ltions connecting sai said socket for preventing the unscrewing of said lamp under conditions of shock vibration.

4. A locking device for incandescent lamps comprising in combination with a screw threaded socket an incandescent lamp having a screw threaded base adapted to engage said socket, a plurality of indentations formed in said screw threaded base,a' wire like member doubled upon itself and encircling' the screw threads on said screw threaded vsocket and passing through one wallthereof for engaging the indentations on said screw threaded base when said incandescent lamp is screwed into said socket for preventing the unscrewing of said incandescent lamp from the socket under conditions of shock vibration.

5. A locking device for incandescent lamps comprising in combination with a screw threaded socket an incandescent lamp having a screw threaded base adapted to en` gage said socket, a plurality of indentations formed in said screw threaded base, a wire like member bent upon itself and having a pitch substantially equal to the pitch of the screw threads on said socket, said wire member having a substantially square nose portion and a pair of (parallel extending pornose portion and embracing the exterior'screw threads of said socket and extending through one wall thereof for engaging the indentations on said base when said incandescent lamp is screwed into said socket, whereby said 1am is prevented from unscrewing from said soc et under conditions of shock vibration.

6. A locking device for incandescent lamps having a screw threaded socket ar- 'ranged to receive an incandescent lamp having a screw threaded base, a plurality of indentations formed' in said screw threaded base, a wire member bent into substantially a U shaped forni and arranged to encircle the exterior of the screw threads of said socket with the U shaped head of said wire niember passing through one wall 0f said socket for engaging the indentations formed in the base of said lamp when the said lamp is screwed into said socket, whereby said lamp is prevented from unscrewing from said socket under conditions of shock vibration.

In testimony whereof I affix my signature.

FREEMAN H. OWENS. 

